/*

 * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.security.mscapi;

import java.io.ByteArrayInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.security.AccessController;

import java.security.InvalidKeyException;

import java.security.Key;

import java.security.KeyStoreSpi;

import java.security.KeyStoreException;

import java.security.PrivilegedAction;

import java.security.UnrecoverableKeyException;

import java.security.NoSuchAlgorithmException;

import java.security.SecurityPermission;

import java.security.cert.X509Certificate;

import java.security.cert.Certificate;

import java.security.cert.CertificateException;

import java.security.cert.CertificateFactory;

import java.security.interfaces.RSAPrivateCrtKey;

import java.util.*;

/**

 * Implementation of key store for Windows using the Microsoft Crypto API.

 *

 * @since 1.6

 */

abstract class CKeyStore extends KeyStoreSpi {

    public static final class MY extends CKeyStore {

        public MY() {

            super("MY");

        }

    }

    public static final class ROOT extends CKeyStore {

        public ROOT() {

            super("ROOT");

        }

    }

    class KeyEntry {

        private CKey privateKey;

        private X509Certificate[] certChain;

        private String alias;

        KeyEntry(CKey key, X509Certificate[] chain) {

            this(null, key, chain);

        }

        KeyEntry(String alias, CKey key, X509Certificate[] chain) {

            this.privateKey = key;

            this.certChain = chain;

            /*

             * The default alias for both entry types is derived from a

             * hash value intrinsic to the first certificate in the chain.

             */

             if (alias == null) {

                 this.alias = Integer.toString(chain[0].hashCode());

             } else {

                 this.alias = alias;

             }

        }

        /**

         * Gets the alias for the keystore entry.

         */

        String getAlias() {

            return alias;

        }

        /**

         * Sets the alias for the keystore entry.

         */

        void setAlias(String alias) {

            // TODO - set friendly name prop in cert store

            this.alias = alias;

        }

        /**

         * Gets the private key for the keystore entry.

         */

        CKey getPrivateKey() {

            return privateKey;

        }

        /**

         * Sets the private key for the keystore entry.

         */

        void setRSAPrivateKey(Key k)

            throws InvalidKeyException, KeyStoreException {

            RSAPrivateCrtKey key = (RSAPrivateCrtKey) k;

            byte[] modulusBytes = key.getModulus().toByteArray();

            // Adjust key length due to sign bit

            int keyBitLength = (modulusBytes[0] == 0)

                    ? (modulusBytes.length - 1) * 8

                    : modulusBytes.length * 8;

            byte[] keyBlob = generateRSAPrivateKeyBlob(

                    keyBitLength,

                    modulusBytes,

                    key.getPublicExponent().toByteArray(),

                    key.getPrivateExponent().toByteArray(),

                    key.getPrimeP().toByteArray(),

                    key.getPrimeQ().toByteArray(),

                    key.getPrimeExponentP().toByteArray(),

                    key.getPrimeExponentQ().toByteArray(),

                    key.getCrtCoefficient().toByteArray());

            privateKey = storePrivateKey("RSA", Objects.requireNonNull(keyBlob),

                    "{" + UUID.randomUUID().toString() + "}", keyBitLength);

        }

        /**

         * Gets the certificate chain for the keystore entry.

         */

        X509Certificate[] getCertificateChain() {

            return certChain;

        }

        /**

         * Sets the certificate chain for the keystore entry.

         */

        void setCertificateChain(X509Certificate[] chain)

                throws CertificateException, KeyStoreException {

            for (int i = 0; i < chain.length; i++) {

                byte[] encoding = chain[i].getEncoded();

                if (i == 0 && privateKey != null) {

                    storeCertificate(getName(), alias, encoding,

                        encoding.length, privateKey.getHCryptProvider(),

                        privateKey.getHCryptKey());

                } else {

                    storeCertificate(getName(), alias, encoding,

                        encoding.length, 0L, 0L); // no private key to attach

                }

            }

            certChain = chain;

        }

    }

    /*

     * An X.509 certificate factory.

     * Used to create an X.509 certificate from its DER-encoding.

     */

    private CertificateFactory certificateFactory = null;

    /*

     * Compatibility mode: for applications that assume keystores are

     * stream-based this mode tolerates (but ignores) a non-null stream

     * or password parameter when passed to the load or store methods.

     * The mode is enabled by default.

     */

    private static final String KEYSTORE_COMPATIBILITY_MODE_PROP =

        "sun.security.mscapi.keyStoreCompatibilityMode";

    private final boolean keyStoreCompatibilityMode;

    /*

     * The keystore entries.

     * Keys in the map are unique aliases (thus can differ from

     * KeyEntry.getAlias())

     */

    private Map<String,KeyEntry> entries = new HashMap<>();

    /*

     * The keystore name.

     * Case is not significant.

     */

    private final String storeName;

    CKeyStore(String storeName) {

        // Get the compatibility mode

        String prop = AccessController.doPrivileged(

            (PrivilegedAction<String>) () -> System.getProperty(KEYSTORE_COMPATIBILITY_MODE_PROP));

        if ("false".equalsIgnoreCase(prop)) {

            keyStoreCompatibilityMode = false;

        } else {

            keyStoreCompatibilityMode = true;

        }

        this.storeName = storeName;

    }

    /**

     * Returns the key associated with the given alias.

     * <p>

     * A compatibility mode is supported for applications that assume

     * a password must be supplied. It permits (but ignores) a non-null

     * <code>password</code>.  The mode is enabled by default.

     * Set the

     * <code>sun.security.mscapi.keyStoreCompatibilityMode</code>

     * system property to <code>false</code> to disable compatibility mode

     * and reject a non-null <code>password</code>.

     *

     * @param alias the alias name

     * @param password the password, which should be <code>null</code>

     *

     * @return the requested key, or null if the given alias does not exist

     * or does not identify a <i>key entry</i>.

     *

     * @exception NoSuchAlgorithmException if the algorithm for recovering the

     * key cannot be found,

     * or if compatibility mode is disabled and <code>password</code> is

     * non-null.

     * @exception UnrecoverableKeyException if the key cannot be recovered.

     */

    public java.security.Key engineGetKey(String alias, char[] password)

        throws NoSuchAlgorithmException, UnrecoverableKeyException {

        if (alias == null) {

            return null;

        }

        if (password != null && !keyStoreCompatibilityMode) {

            throw new UnrecoverableKeyException("Password must be null");

        }

        if (engineIsKeyEntry(alias) == false)

            return null;

        KeyEntry entry = entries.get(alias);

        return (entry == null)

                ? null

                : entry.getPrivateKey();

    }

    /**

     * Returns the certificate chain associated with the given alias.

     *

     * @param alias the alias name

     *

     * @return the certificate chain (ordered with the user's certificate first

     * and the root certificate authority last), or null if the given alias

     * does not exist or does not contain a certificate chain (i.e., the given

     * alias identifies either a <i>trusted certificate entry</i> or a

     * <i>key entry</i> without a certificate chain).

     */

    public Certificate[] engineGetCertificateChain(String alias) {

        if (alias == null) {

            return null;

        }

        KeyEntry entry = entries.get(alias);

        X509Certificate[] certChain = (entry == null)

                ? null

                : entry.getCertificateChain();

        return (certChain == null)

                ? null

                : certChain.clone();

    }

    /**

     * Returns the certificate associated with the given alias.

     *

     * <p>If the given alias name identifies a

     * <i>trusted certificate entry</i>, the certificate associated with that

     * entry is returned. If the given alias name identifies a

     * <i>key entry</i>, the first element of the certificate chain of that

     * entry is returned, or null if that entry does not have a certificate

     * chain.

     *

     * @param alias the alias name

     *

     * @return the certificate, or null if the given alias does not exist or

     * does not contain a certificate.

     */

    public Certificate engineGetCertificate(String alias) {

        if (alias == null) {

            return null;

        }

        KeyEntry entry = entries.get(alias);

        X509Certificate[] certChain = (entry == null)

                ? null

                : entry.getCertificateChain();

        return (certChain == null || certChain.length == 0)

                ? null

                : certChain[0];

    }

    /**

     * Returns the creation date of the entry identified by the given alias.

     *

     * @param alias the alias name

     *

     * @return the creation date of this entry, or null if the given alias does

     * not exist

     */

    public Date engineGetCreationDate(String alias) {

        if (alias == null) {

            return null;

        }

        return new Date();

    }

    /**

     * Stores the given private key and associated certificate chain in the

     * keystore.

     *

     * <p>The given java.security.PrivateKey <code>key</code> must

     * be accompanied by a certificate chain certifying the

     * corresponding public key.

     *

     * <p>If the given alias already exists, the keystore information

     * associated with it is overridden by the given key and certificate

     * chain. Otherwise, a new entry is created.

     *

     * <p>

     * A compatibility mode is supported for applications that assume

     * a password must be supplied. It permits (but ignores) a non-null

     * <code>password</code>.  The mode is enabled by default.

     * Set the

     * <code>sun.security.mscapi.keyStoreCompatibilityMode</code>

     * system property to <code>false</code> to disable compatibility mode

     * and reject a non-null <code>password</code>.

     *

     * @param alias the alias name

     * @param key the private key to be associated with the alias

     * @param password the password, which should be <code>null</code>

     * @param chain the certificate chain for the corresponding public

     *        key (only required if the given key is of type

     *        <code>java.security.PrivateKey</code>).

     *

     * @exception KeyStoreException if the given key is not a private key,

     * cannot be protected, or if compatibility mode is disabled and

     * <code>password</code> is non-null, or if this operation fails for

     * some other reason.

     */

    public void engineSetKeyEntry(String alias, java.security.Key key,

            char[] password, Certificate[] chain) throws KeyStoreException {

        if (alias == null) {

            throw new KeyStoreException("alias must not be null");

        }

        if (password != null && !keyStoreCompatibilityMode) {

            throw new KeyStoreException("Password must be null");

        }

        if (key instanceof RSAPrivateCrtKey) {

            KeyEntry entry = entries.get(alias);

            X509Certificate[] xchain;

            if (chain != null) {

                if (chain instanceof X509Certificate[]) {

                    xchain = (X509Certificate[]) chain;

                } else {

                    xchain = new X509Certificate[chain.length];

                    System.arraycopy(chain, 0, xchain, 0, chain.length);

                }

            } else {

                xchain = null;

            }

            if (entry == null) {

                entry =

                    //TODO new KeyEntry(alias, key, (X509Certificate[]) chain);

                    new KeyEntry(alias, null, xchain);

                storeWithUniqueAlias(alias, entry);

            }

            entry.setAlias(alias);

            try {

                entry.setRSAPrivateKey(key);

                entry.setCertificateChain(xchain);

            } catch (CertificateException ce) {

                throw new KeyStoreException(ce);

            } catch (InvalidKeyException ike) {

                throw new KeyStoreException(ike);

            }

        } else {

            throw new UnsupportedOperationException(

                "Cannot assign the key to the given alias.");

        }

    }

    /**

     * Assigns the given key (that has already been protected) to the given

     * alias.

     *

     * <p>If the protected key is of type

     * <code>java.security.PrivateKey</code>, it must be accompanied by a

     * certificate chain certifying the corresponding public key. If the

     * underlying keystore implementation is of type <code>jks</code>,

     * <code>key</code> must be encoded as an

     * <code>EncryptedPrivateKeyInfo</code> as defined in the PKCS #8 standard.

     *

     * <p>If the given alias already exists, the keystore information

     * associated with it is overridden by the given key (and possibly

     * certificate chain).

     *

     * @param alias the alias name

     * @param key the key (in protected format) to be associated with the alias

     * @param chain the certificate chain for the corresponding public

     * key (only useful if the protected key is of type

     * <code>java.security.PrivateKey</code>).

     *

     * @exception KeyStoreException if this operation fails.

     */

    public void engineSetKeyEntry(String alias, byte[] key,

                                  Certificate[] chain)

            throws KeyStoreException {

        throw new UnsupportedOperationException(

            "Cannot assign the encoded key to the given alias.");

    }

    /**

     * Assigns the given certificate to the given alias.

     *

     * <p>If the given alias already exists in this keystore and identifies a

     * <i>trusted certificate entry</i>, the certificate associated with it is

     * overridden by the given certificate.

     *

     * @param alias the alias name

     * @param cert the certificate

     *

     * @exception KeyStoreException if the given alias already exists and does

     * not identify a <i>trusted certificate entry</i>, or this operation

     * fails for some other reason.

     */

    public void engineSetCertificateEntry(String alias, Certificate cert)

            throws KeyStoreException {

        if (alias == null) {

            throw new KeyStoreException("alias must not be null");

        }

        if (cert instanceof X509Certificate) {

            // TODO - build CryptoAPI chain?

            X509Certificate[] chain =

                new X509Certificate[]{ (X509Certificate) cert };

            KeyEntry entry = entries.get(alias);

            if (entry == null) {

                entry =

                    new KeyEntry(alias, null, chain);

                storeWithUniqueAlias(alias, entry);

            }

            if (entry.getPrivateKey() == null) { // trusted-cert entry

                entry.setAlias(alias);

                try {

                    entry.setCertificateChain(chain);

                } catch (CertificateException ce) {

                    throw new KeyStoreException(ce);

                }

            }

        } else {

            throw new UnsupportedOperationException(

                "Cannot assign the certificate to the given alias.");

        }

    }

    /**

     * Deletes the entry identified by the given alias from this keystore.

     *

     * @param alias the alias name

     *

     * @exception KeyStoreException if the entry cannot be removed.

     */

    public void engineDeleteEntry(String alias) throws KeyStoreException {

        if (alias == null) {

            throw new KeyStoreException("alias must not be null");

        }

        KeyEntry entry = entries.remove(alias);

        if (entry != null) {

            // Get end-entity certificate and remove from system cert store

            X509Certificate[] certChain = entry.getCertificateChain();

            if (certChain != null && certChain.length > 0) {

                try {

                    byte[] encoding = certChain[0].getEncoded();

                    removeCertificate(getName(), entry.getAlias(), encoding,

                            encoding.length);

                } catch (CertificateException e) {

                    throw new KeyStoreException("Cannot remove entry: ", e);

                }

            }